1. Field of the Invention
The present invention relates to liquid crystal display (LCD), and more particularly, to a circuit capable of improving a shift of a gamma curve resulting from light emitting diode (LED) temperature rise and a device thereof.
2. Description of the Prior Art
LCDs have gradually become the mainstream in the display device market. An LCD does not generate light itself; instead, lighting components serve as LCD backlights. Light emitting diodes (LEDs) are often used in conventional LCD backlights. LED temperature may rise or fall, depending on the environment where LEDs are used, the duration of use, and so on, leading to a change in luminescence spectra from LEDs. Once the LED temperature rises, the proportions of pixels comprising three sun-pixels of Red, Green, and Blue is changed as well. This will causes a shift of the gamma curve and variations in images, thereby affecting overall viewing quality.
In order to solve the problem that image quality degrades because of a rise in the LED temperature, the conventional technology adopts a hardware circuit. For example, Chinese Patent application No. 200920132222.3 proposes a backlight module and an LCD device and an LCD television set thereof. An LCD panel driving circuit is coupled to a temperature sensor responsive to a sensing signal for regulating driving voltage. The LCD panel is driven based on the regulated driving voltage. However, the problem with the conventional technology lies in the fact that the illumination of LEDs is adjusted indirectly through the driving voltage. Because of this reason, the gamma curve cannot be regulated directly and precisely; image quality cannot be effectively improved, either.
Therefore, it is a considerable need for providing a circuit capable of correcting a shift of the gamma curve resulting from LED temperature rise and a device thereof for solving the problem of the conventional technology described above. The problem is that the illumination of LEDs is adjusted indirectly through the driving voltage, so the gamma curve cannot be adjusted directly and precisely, causing image quality to be unable to be effectively improved.